"any" is quite an assumption.
Sometimes they're available, but not palatable, when the opportunity could threaten their existing investments or patterns. That might mean "self-cannibalism", or changing the ecology so that the main product niche is threatened.
Then those opportunities are ignored, or actively worked-against via lobbying, embrace-extend-extinguish, etc.
Whether the reason of strategic (like your example), internal politics, insufficient knowledge.... The point is that there is a local equilibrium, and most mature firms are at this equilibrium.
More resources via Ai, at first order, goes after that diminishing returns part of the curve... which is a cliff especially for highly resourced firms topping the S&P500.
A lot of Ai-optimist:s " mental model" of the economy do not account for this stuff at all.
"Save time/money" outcomes are not similar at all to "make more stuff" outcomes. Firing employees does freeze up labour... but reutilizing this labour is non-trivial... as this article demonstrates quite well.